1. Field of the Invention
The present invention relates generally to antenna orientation, and in particular to a system and method for cellular telecommunications antenna orientation using tilt sensors.
2. Description of the Related Art
Antennas are commonly installed on structures, such as buildings and towers, at a height above the surface of the earth thereby permitting broadcast communication over a wide area. Some antennas are directional antennas requiring precise installation and orientation for optimal system performance. For example, the type of orientation that affects antenna broadcast communications include azimuth, elevation tilt, and slant. Therefore, depending upon the quantity and orientation of an array of antennas, each antenna will have an independent orientation in order to provide optimal performance.
Telecommunication antennas are typically directional antennas housed within an elongated enclosure. Previously, telecommunication antenna orientation was accomplished manually by conducting a rough approximation from ground level, e.g., by surveyors, followed by an antenna-level fine adjustment consisting of reorientation of the antenna enclosure by skilled technicians using special equipment and techniques. Such manual antenna orientation and adjustment procedures had a number of disadvantages. For example, they tended to be relatively expensive because the technicians were relatively highly-trained, and the equipment was relatively sophisticated. Moreover, determining antenna orientation at any given point in time required technicians to ascend a structure, individually assess antenna orientation and adjust the antenna position, one-by-one, using iterative procedures, which tended to be time-consuming, particularly for installations consisting of a number of antennas.
Another approach to manual telecommunication antenna orientation and adjustment uses the global navigation satellite system (GNSS, including GPS) receiver dishes mounted on frames, which in turn are temporarily mounted on the antennas for conducting azimuth, elevation tilt and slant orientation and adjustment of the antenna. The Boucher U.S. Pat. No. 6,897,828 and No. 7,180,471 are examples of such an approach. Multiple GPS receiver dishes in a predetermined spaced relation can be used for computing orientation of an antenna by triangulating the GPS signals, or a single GPS receiver dish can be moved from one location to another. However, the GPS receiver dishes and the frames on which they are mounted must be relocated for each separate antenna orientation and adjustment. Subsequent antenna adjustments require technicians to ascend the transmission structure to reattach the GPS equipment to the individual antenna enclosures in order to obtain orientation readings in real-time, followed by manual reorientation of the antenna by adjusting the mountings accordingly.
A significant disadvantage associated with the aforementioned and other previous antenna orientation and adjustment devices and methods involve their inability to continuously monitor antenna orientation and detect disorientation from a baseline orientation. Cellular telecommunications antennas are susceptible to physical disorientation from various causes, such as meteorological, geological, and other impact forces. For example, forces generated during a major storm may change the orientation of antenna housings on telecommunications towers and in other installations within an entire region resulting in communications performance degradation. Consequently, identification of antennas in need of reorientation, and reorientation of each affected antenna would require individualized physical attention from a technician. Therefore, an antenna orientation and adjustment system and method should not only facilitate initial orientation, but also facilitate ongoing orientation monitoring with an ability to detect conditions of disorientation, thereby requiring limited physical visits by technicians to antenna installations, and limited need for specialized equipment in order to effectuate installation and orientation of telecommunications antenna. Moreover, an antenna orientation system and method should be adaptable to existing antenna equipment permitting ease of installation and compliance with stringent regulatory requirements and approval procedures.
Heretofore there has not been available an antenna orientation system and method with the advantages and features of the present invention.